Solvent-Free Iridium-Catalyzed Reactivity of CO2 with Secondary Amines and Hydrosilanes

The complex [Ir(H)(CF3SO3)(NSiN)(coe)] (NSiN=bis(pyridine-2-yloxy) methylsilyl fac-coordinated) (1) is an effective catalyst precursor for the solvent-free synthesis of silyl carbamates from reaction of aliphatic secondary amines with CO2 and HSiMe(OSiMe3)(2). The preferential formation of the silyl carbamate instead of the expected formamide or methylamine has proven to be consequence of an iridium-catalyzed dehydrogenative Si-N coupling between the silane and the amine to afford the corresponding silyl amine, which under the reaction conditions reacts with CO2 to give the corresponding silyl carbamate.